Having another seizure despite taking epilepsy medicine can be frustrating and frightening. But one breakthrough seizure does not automatically mean that treatment has failed, and continuing seizures do not always mean that a person has drug-resistant epilepsy.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
The first step is to understand why the seizures are still happening. Possible reasons include:
- The medicine or dose is not suitable for the seizure type
- doses have been missed or taken inconsistently
- The epilepsy diagnosis or seizure classification needs review
- Another medicine is interfering with treatment
- Sleep deprivation, alcohol or illness is lowering the seizure threshold
- The epilepsy is genuinely resistant to antiseizure medicines
For a broader overview of available therapies, see our main guide to Epilepsy Treatment.
What Are Uncontrolled Seizures?
Uncontrolled seizures generally mean that seizures continue despite treatment or are occurring more frequently or severely than expected. This can include:
- Breakthrough seizures after a period of good control
- Repeated focal seizures
- Generalised tonic-clonic seizures despite medication
- Seizure clusters
- Seizures that continue despite trying more than one appropriate medicine
The term does not automatically tell us why the seizures remain uncontrolled. That distinction matters because the treatment for missed medication is very different from the treatment for true drug-resistant epilepsy.
Step 1: Confirm That the Events Are Epileptic Seizures
When seizures continue despite an appropriate dose of a first-line medicine, current guidance recommends reviewing the diagnosis. Several conditions can sometimes resemble epileptic seizures, including:
- Fainting
- Heart rhythm disturbances
- Sleep disorders
- Migraine-related events
- Movement disorders
- Dissociative or functional seizures
When the diagnosis remains uncertain, evaluation may include:
- A detailed description of what happens before, during and after the event
- Videos recorded safely by family members when available
- EEG
- Brain MRI
- Prolonged or video EEG monitoring
Step 2: Check Whether the Medicine Is Being Taken Consistently
Missed doses are one of the most important preventable reasons for breakthrough seizures. Antiseizure medicines work best when the level of medication in the body remains reasonably consistent. Seizures can sometimes return when:
- Doses are forgotten
- Medication is stopped suddenly
- The timing of doses varies significantly
- A prescription runs out
- Vomiting prevents medicine from being absorbed
Step 3: Review the Dose and Treatment Response
Sometimes the correct medicine has been prescribed but an adequate therapeutic trial has not yet occurred. The neurologist may consider:
- Whether the dose can safely be increased
- Whether enough time has been allowed to judge the response
- Whether side effects prevent further dose increases
- Whether another medicine would provide a better balance of effectiveness and tolerability
Before Calling Epilepsy Drug Resistant: Look for Reversible Causes
Doctors sometimes use the term pseudo-resistance when seizures appear resistant to medication but another correctable factor is preventing good control. Examples include:
- An incorrect epilepsy diagnosis
- The wrong seizure type being treated
- An unsuitable antiseizure medicine
- Medication being taken inconsistently
- An inadequate dose
- Important drug interactions
- Heavy alcohol use
- Severe sleep deprivation
When Does Uncontrolled Epilepsy Become Drug Resistant?
This is one of the most important milestones in epilepsy care. The International League Against Epilepsy defines drug-resistant epilepsy as failure of: Two tolerated, appropriately chosen and adequately used antiseizure medication schedules to achieve sustained seizure freedom.
The two treatments can have been used:
- One after another as monotherapy
- Or in an appropriate combination
Epilepsy Surgery for Uncontrolled Focal Seizures
For appropriately selected patients with drug-resistant focal epilepsy, epilepsy surgery can provide the best opportunity for long-term seizure freedom. Surgery is most useful when doctors can identify a brain region that:
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
- Consistently produces the seizures
- Can be safely removed or disconnected without causing unacceptable loss of important brain function
A surgical evaluation may include:
- Video EEG monitoring
- High-resolution MRI
- Neuropsychological testing
- PET or SPECT imaging in selected cases
- Functional brain mapping
- Intracranial EEG in selected complex cases
What If Epilepsy Surgery Is Not Possible?
Not every patient's seizures arise from an area that can safely be removed. Other specialist treatment options can then be considered.
Vagus Nerve Stimulation
Vagus nerve stimulation (VNS) uses an implanted device to send regular electrical signals through the vagus nerve in the neck. It is generally considered as an add-on treatment when drug-resistant seizures continue and resective epilepsy surgery is unsuitable. VNS more commonly reduces seizure frequency or severity than produces complete seizure freedom.
Other Neuromodulation Treatments
Depending on the country and type of epilepsy, specialist centres may also consider treatments such as:
- Deep brain stimulation (DBS)
- Responsive neurostimulation (RNS)
Rescue Treatment for Seizure Clusters or Prolonged Seizures
Some people with poorly controlled epilepsy experience seizure clusters or seizures that last longer than usual. They may be given an individualised emergency seizure plan.
The plan may include a fast-acting rescue benzodiazepine such as buccal or intranasal midazolam or another locally appropriate rescue medicine. Rescue medication is different from daily antiseizure treatment. Its purpose is to stop a prolonged seizure or cluster before it develops into a more dangerous emergency.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
When Does an Uncontrolled Seizure Become an Emergency?
A convulsive seizure lasting 5 minutes or longer should be treated as convulsive status epilepticus and requires emergency treatment. Emergency help is also needed when:
- Convulsive seizures continue without normal recovery between them
- A person has repeated or cluster seizures according to their emergency plan
- Breathing remains abnormal after the seizure
- A serious injury has occurred
- The seizure happens in water
- The person is pregnant
- The seizure is substantially longer than that person's usual episodes
Practical Steps When Seizures Are Still Happening
| Problem | Possible Next Step |
|---|---|
| Breakthrough seizure after missed medication | Address adherence and discuss whether treatment needs reassessment |
| Seizures continue on first medicine | Review diagnosis, seizure type, dose and treatment choice |
| First appropriate medicine fails | Try another suitable monotherapy or add-on treatment |
| Two appropriate medication schedules fail | Evaluate for drug-resistant epilepsy and refer to a tertiary epilepsy centre |
| Drug-resistant focal epilepsy | Consider epilepsy surgery assessment |
| Surgery is unsuitable | Consider VNS or other specialist neuromodulation options |
| Selected drug-resistant epilepsy | Consider specialist ketogenic dietary therapy |
| Prolonged or cluster seizures | Use an individualised rescue plan and seek emergency care when indicated |
Common Mistakes When Seizures Remain Uncontrolled
- Increasing medicine without confirming the seizure diagnosis
- Stopping medication suddenly because it seems ineffective
- Hiding missed doses from the healthcare team
- Assuming every antiseizure medicine works for every epilepsy type
- Repeatedly changing medicines without reviewing the diagnosis
- Waiting through many medication failures before considering specialist referral
- Treating seizure clusters at home without an appropriate emergency plan
- Replacing evidence-based treatment with supplements or alternative therapies
The Bottom Line
Treatment for uncontrolled seizures starts by finding out why the seizures are still occurring. Doctors should first review the epilepsy diagnosis, seizure type, medication choice, dose, adherence, possible interactions and avoidable triggers. If one appropriate antiseizure medicine does not work, another suitable medicine can usually be tried, either as replacement monotherapy or as add-on treatment.
However, when two tolerated, appropriately chosen and adequately used antiseizure medication schedules fail to achieve sustained seizure freedom, the epilepsy meets the recognised definition of drug-resistant epilepsy.
At that point, referral to a tertiary epilepsy service becomes particularly important. Selected patients with drug-resistant focal epilepsy may benefit substantially from epilepsy surgery. When resective surgery is unsuitable, treatment options can include further specialist medication, vagus nerve stimulation or other neuromodulation approaches, and medically supervised ketogenic dietary therapy. Patients who experience prolonged seizures or seizure clusters may also need a personalised emergency plan and rescue medication.
Most importantly: Uncontrolled seizures should not simply lead to endless medication changes. The diagnosis and treatment strategy should be reassessed, and once drug resistance is established, specialist options should be considered without unnecessary delay.
